Being a go teacher and reviewing a lot of games, he identified seven stereotypes among kyu players :
The Philosopher: knows a lot of things, principles and theories... but thinks too much
The Honor student: make good shape and is strong at basics... but lacks experience and fighting spirit
The Politician: good at negotiations
The Boss: bullies his/her opponent, have him/her do the hard work
The Detective: strong at tesuji and finding the weakness in opponents' position
The Street Fighter: strong at fighting, plays fast, but lacks the basic knowledge
The Don Quichotte: creative, but the game quality depends on the day
Here's the video. Very funny, with a lot of examples taken from real games. The lecture starts at 6:40